Log in

View Full Version : DEF Adblue tank ultrasonic sensor failure



Starry
29th March 2025, 06:25 AM
Hello AULRO team,

I was previously subscribed to AULRO as we has a Discovery 3 for 10 years (2009 to 2019) before buying a near new 2017 Discovery 5 Td6 HSE. Having not logged on for a long while, I‘ve rejoined hence this is my first post under this name.

Unfortunately, we have the dreaded message regarding 500km remaining due to low DEF/Adblue, despite the tank being filled after receiving this message some months ago (but not to the brim). The LR dealer has reset the sensor which helped for a while but the problem has returned. Their diagnosis is that the Adblue tank has previously been filled to the brim which caused failure of the ultrasonic sensor.

The proposed LR fix is replacement of the whole adblue tank and sensor quoted at $4000 (parts and labour)!

I love driving this car (when it works), but I am getting tired of the LR tax of ownership where they just want to throw excessive new parts at a problem rather than repairing it.

Has anyone else here had the same problem?

Is it possible to just buy the ultrasonic sensor?

Thank you for your assistance.

Regards,

Andrew

oldyella 76
5th April 2025, 07:51 PM
Join the facebook discovery 5 Australia group, there are some more owners on there with a lot of knowledge.
I did and find it quite valuable. Just make sure it is the Australian group as there is a pommy group as well.
Lindsay

Starry
17th April 2025, 06:22 PM
Just posting a follow up for anyone else who experiences this problem.

I purchased a replacement Adblue/DEF tank and installed it today and added 5litres of Adblue fluid.

Upon starting the car, the ‘no starts in XXXkms’ disappeared but the engine light remained on.

I used my AUSCAN diagnostic tool to check the Adblue level (reading 5.5l) and then re-primed the system (7 minute procedure with the scan tool).

Once completed, I cleared the fault codes and the engine light turned off.

Took it for a long drive and it is back to normal.

The lesson for the day - don’t overfill your Adblue tank because you can damage the sensor and it may require replacement. You can’t buy the sensor separately as far as I know, so it is an expensive and time consuming lesson.

Regards,

Andrew